We present new Hubble Space Telescope STIS, high-resolution optical imaging of a sample of 13 submillimeter (submm) luminous galaxies, for which the optical emission has been pinpointed either through radio-1.4 GHz or millimeter interferometry. We find a predominance of irregular and complex morphologies in the sample, suggesting that mergers are likely common for submm galaxies. The component separation in these objects are on average a factor two larger than local galaxies with similarly high bolometric luminosities. The sizes and star formation rates of the submm galaxies are consistent with the maximal star formation rate densities of 20 M ⊙ kpc −2 in local starburst galaxies (Lehnert & Heckman 1996). We derive quantitative morphological information for the optical galaxies hosting the submm emission; total and isophotal magnitudes, Petrosian radius, effective radius, concentration, aspect ratio, surface brightness, and asymmetry. We compare these morphological indices with those of other galaxies lying within the same STIS images. Most strikingly, we find ∼70% of the submm galaxies to be extraordinarily large and elongated relative to the field population, regardless of optical magnitude. Comparison of the submm galaxy morphologies with those of optically selected galaxies at z ∼ 2 − 3 reveal the submm galaxies to be a morphologically distinct population, with generally larger sizes, higher concentrations and more prevalent major-merger configurations.

For quality control of textiles, it is necessary to develop an objective method to evaluate fabric pilling, rather than subjective, to improve reliability and reproducibility. This paper presents a new method to extract pill features from fabric images. In this work, we apply a two-dimensional Gaussian fit theory to train a pill template using actual pill images for pill template matching, and determine a reasonable threshold for image segmentation using a histogram-fitting technique. We then extract five parameters to describe pill properties—pill number, mean area of pills. total area of pills. contrast. and density—and establish formulas to calculate objective grades with these parameters. The results show that a good correlation can be achieved between objective and subjective data.Pilling on fabrics is a well-known phenomenon, and such an unpleasant appearance can seriously compromise a fabric's acceptability. Pilling is an effect caused by wear and tear that considerably spoils the original appearance of a fabric. It begins with migration of fibers to the external parts of yarns, so that fuzz emerges on the fabric surface. Due to friction, this fuzz gets entangled, forming pills that remain suspended from the fabric by long fibers. Pills develop on a fabric surface in four stages: fuzz formation, entanglement, growth, and wearoff (Cooke, 1985) [2]. Fabric pilling is commonly tested in the laboratory by using specific machines to generate pills. These machines are usually supplied with a stan-. dard consisting of photographs of samples with different degree of pilling. Experts with long training and experience assign a degree of pilling by looking at the sample processed by the machine. However, a common drawback of these subjective methods based on estimations by experts is their inconsistency and the inaccuracy of the rating results.Great improvement can be achieved by introducing image analysis techniques, which have been widely used for characterizing and inspecting general textured materials and, in particular, textile materials [ 1. 7. 12]. Previous valuable works on pilling evaluations by digital image analysis have been reported in references 3, 4, 5, 7, 8, 9. 11. One-way of acquiring surface data from a fabric specimen is for a laser probe to measure surface height variation, as was pointed out by Ramgulam et al. [7]. Laser-scanning techniques can acquire 3D fabric depth images to avoid the difficulty of identifying pills on a patterned fabric. However, this kind of scanning process makes data acquisition much slower than camera capturing. since it needs an x -v stage to transport the sample mechanically. In this situation, a video camera. together with an effective algorithm to identify pills. is still of great research and practical value. Konda er al. (i988) [5] used a video camera and almost tangential illumination to capture samples. and Hsi et al. (1998) (4] found that a diffuse light source is much more suitable for pilling identification than collimated lighting. These groups i...

Measurements of the solubility curve of a quasi-monodisperse gold nanoparticle solution are given. Temperature quenches from the one-phase to the two-phase regime yielded superclusters of the nanoparticle solid phase with sizes that depended on the quench depth. Classical nucleation theory was used to describe these sizes using a value of the surface tension for the nanoparticle solid phase of 0.042 erg/cm2. This value is consistent with molecule size scaling of the surface tension. In total these results show that suspensions of nanoparticles act like molecular solutions.

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Newcastle disease caused by ND virus (NDV) is a highly contagious disease of birds. Vaccine for effective protection of poultry animals from NDV infection is urgently needed. Mucosal immunity plays a very important role in the antiviral immune response. In this study, a NDV F gene-containing DNA vaccine encapsulated in Ag@SiO2 hollow nanoparticles (pFDNA-Ag@SiO2-NPs) with an average diameter of 500 nm were prepared to assess the mucosal immune response. These nanoparticles exhibited low cytotoxicity and did not destroy the bioactivity of plasmid DNA, which could be expressed in vitro. The plasmid DNA was sustainably released after an initial burst release. In vivo immunization showed that the intranasal immunization of chickens with pFDNA-Ag@SiO2-NPs induced high titers of serum antibody, significantly promoted lymphocyte proliferation and induced higher expression levels of IL-2 and IFN-γ in a dose-dependent manner. These results indicated that the Ag@SiO2 hollow nanoparticles could serve as an efficient and safe delivery carrier for NDV DNA vaccine to induce mucosal immunity. This study has provided promising results for the further development of mucosal vaccines encapsulated in inorganic nanoparticles.